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      <div><h1><span class="kind-method">computeLuminance</span> method</h1></div>

    <section class="multi-line-signature">
      <span class="returntype"><a href="dart-core/double-class.html">double</a></span>
            <span class="name ">computeLuminance</span>
(<wbr>)
      
    </section>
    <section class="desc markdown">
      <p>Returns a brightness value between 0 for darkest and 1 for lightest.</p>
<p>Represents the relative luminance of the color. This value is computationally
expensive to calculate.</p>
<p>See <a href="https://en.wikipedia.org/wiki/Relative_luminance">en.wikipedia.org/wiki/Relative_luminance</a>.</p>
    </section>
    
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      <h2><span>Implementation</span></h2>
      <pre class="language-dart"><code class="language-dart">double computeLuminance() {
  &#47;&#47; See &lt;https:&#47;&#47;www.w3.org&#47;TR&#47;WCAG20&#47;#relativeluminancedef&gt;
  final double R = _linearizeColorComponent(red &#47; 0xFF);
  final double G = _linearizeColorComponent(green &#47; 0xFF);
  final double B = _linearizeColorComponent(blue &#47; 0xFF);
  return 0.2126 * R + 0.7152 * G + 0.0722 * B;
}</code></pre>
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